The Pakistani government has confiscated all copies and translations of the book.

“It is interesting that they would say the book contains ‘objectionable materials,’ since it is all scrupulously sourced from texts that Muslims themselves consider reliable,” Spencer told HUMAN EVENTS. “It manifests a certain cultural insecurity that, instead of having a fruitful dialogue or debate about what’s in the book, the Pakistani government just bans and confiscates it.”

In response to questions about the ban, Shahid Ahmed, counselor of community affairs of the Embassy of the Islamic Republic of Pakistan in Washington, D.C., said he had not yet read the latest reports but that “the book is very, very damaging—let me tell you.” He also said the book was ill-sourced.

Spencer said his primary sources for the book were the Koran, the Hadith collections of Bukhari and Muslim, and the two earliest biographies of Muhammad, which, he said, were “both written by pious Muslims: Ibn Ishaq and Ibn Sa’d.”